Serial hybridization, battery-backed mobile electrical generation (decouples load from demand, engine can be run at a higher load for a shorter duration if demand is small), tactical operation including short-term silent electrical supply.

I'd love to see them bring a compact modular range extender to market for consumer applications as well.

Seems like a cool concept. It will be interesting to see if they actually manage to produce anything usable though. Certainly a complex machine. Have you ever heard the phrase "DARPA hard"? Their remit is to pursue projects that are high risk so unlikely to succeed.

I want to see how they deal with IC and electric component packaging on an off-road motorcycle chassis. You would think that finding room for an IC engine of sufficient power to be useful in combat situations, plus a large enough fuel tank to have decent range, plus an electric motor, batteries, transmission, drive-train and other odds and ends would be really challenging. You might be able to stick all of that stuff into a large scooter, but I don't know how it would be done on a dual-sport motorcycle.

One thing that is not mentioned is that all military IC vehicles and equipment now use diesel engines only and typically gasoline is not available in front line theaters. (Note that the current military motorcycle being produced is a Kawasaki DR650 with its engine having been heavily modified as a diesel by a private American company.) So I would imagine that any production version of the hybrid-electric BRD would likely need to be powered by a diesel engine, which would reduce IC performance, increase weight, but also increase fuel efficiency.

The genset and fuel may be stored in one or both of the saddlebags. I'm curious how they'll balance the bike. That also gives them the option of leaving the genset off for higher performance / lower weight as needed.